refactor(runtime): restructure runs module with new execution architecture

Major refactoring of deerflow/runtime/:
- runs/callbacks/ - new callback system (builder, events, title, tokens)
- runs/internal/ - execution internals (executor, supervisor, stream_logic, registry)
- runs/internal/execution/ - execution artifacts and events handling
- runs/facade.py - high-level run facade
- runs/observer.py - run observation protocol
- runs/types.py - type definitions
- runs/store/ - simplified store interfaces (create, delete, query, event)

Refactor stream_bridge/:
- Replace old providers with contract.py and exceptions.py
- Remove async_provider.py, base.py, memory.py

Add documentation:
- README.md and README_zh.md for runtime module

Remove deprecated:
- manager.py moved to internal/
- worker.py, schemas.py
- user_context.py

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/packages/harness/deerflow/runtime/runs/internal/execution/artifacts.py

@@ -0,0 +1,64 @@
+"""Execution preparation helpers for a single run."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Any
+
+from langchain_core.callbacks import BaseCallbackHandler
+from langchain_core.runnables import RunnableConfig
+from langgraph.runtime import Runtime
+
+from deerflow.runtime.stream_bridge import StreamBridge
+
+
+@dataclass
+class RunBuildArtifacts:
+    """Assembled agent runtime pieces for a single run."""
+
+    agent: Any
+    runnable_config: dict[str, Any]
+    reference_store: Any | None = None
+
+
+def build_run_artifacts(
+    *,
+    thread_id: str,
+    run_id: str,
+    checkpointer: Any | None,
+    store: Any | None,
+    agent_factory: Any,
+    config: dict[str, Any],
+    bridge: StreamBridge,
+    interrupt_before: list[str] | None = None,
+    interrupt_after: list[str] | None = None,
+    callbacks: list[BaseCallbackHandler] | None = None,
+) -> RunBuildArtifacts:
+    """Assemble all components needed for agent execution."""
+    runtime = Runtime(context={"thread_id": thread_id}, store=store)
+    if "context" in config and isinstance(config["context"], dict):
+        config["context"].setdefault("thread_id", thread_id)
+    config.setdefault("configurable", {})["__pregel_runtime"] = runtime
+
+    config_callbacks = config.setdefault("callbacks", [])
+    if callbacks:
+        config_callbacks.extend(callbacks)
+
+    runnable_config = RunnableConfig(**config)
+    agent = agent_factory(config=runnable_config)
+
+    if checkpointer is not None:
+        agent.checkpointer = checkpointer
+    if store is not None:
+        agent.store = store
+
+    if interrupt_before:
+        agent.interrupt_before_nodes = interrupt_before
+    if interrupt_after:
+        agent.interrupt_after_nodes = interrupt_after
+
+    return RunBuildArtifacts(
+        agent=agent,
+        runnable_config=dict(runnable_config),
+        reference_store=store,
+    )